As broadband network reaches to every home, content distribution is becoming more and more demanding. User is happy with the convenience, and they can enjoy entertainment more easily and efficiently than before.
In a content distribution chain, there are many parties involved in the operation of one content, from content owner, content distributor, to end-user.
First of all, content owner creates contents and postproduction house helps them to encode into certain formats like MPEG-2 or MPEG-4. The content is also protected in an IPMP way, for example, encrypted by certain IPMP tool.
In order to identify, protect and recognise each content, content owner will create usage rules to describe rights for different pieces of content. When content is requested or distributed to user, different usage rules will be applied to different cases based on different business model or strategy. Such usage rules or rights description will be much different from one content distributor to another even for the same content owner.
Traditional IPMP or condition access (hereinafter referred to as CA) system only protects content from content distributor up to the entry point of end-user's home network, for example set-top box (hereinafter referred to as STB) in the case of Digital Video Broadcasting. The prior art of IPMP protection of content is illustrated in FIG. 1.
There is currently no standardized or interoperable way to protect content after content has been retrieved, in particular, content transfer or consumption among devices. There is also no standardized or interoperable way to exchange content or IPMP tool among devices.
Even content is encoded in the same format, like MPEG-4, but it still cannot achieve interoperability due to the different rights description, different usage rules or different places of rights information inside the content.
There is a need to have a standardized way to protect content after content has been retrieved, in particular, content transfer or consumption among devices. We can then have inter-operability among IPMP devices. Hence, there is a need to standardize the way to exchange content or IPMP tool among devices.
There is also a need to standardize a specific place to put rights information (rights description, usage rules) inside an MPEG system, in particular MPEG-4 system.